Dietary Approaches to Stop Hypertension was a feeding study that assessed the effects of dietary patterns on blood pressure in 459 adults with systolic blood pressure <160 mmHg and diastolic blood pressure 80 to 95 mmHg. For three weeks, participants were fed a control diet, low in fruits, vegetables, and dairy products, with fat content typical of US consumption. Participants were then randomized to receive for eight weeks: (1) the control diet, (2) a diet rich in fruits and vegetables, or (3) a "combination" diet rich in fruits, vegetables, and low-fat dairy products, and reduced in saturated and total fat. Sodium and weight were held constant. Compared to control, the combination diet reduced systolic and diastolic blood pressure by 5.5 and 3.0 mmHg (each P<0.001); the fruits and vegetables diet reduced systolic blood pressure by 2.8 mmHg (P<0.001) and diastolic blood pressure by 1.1 mmHg (P=0.07). Among 133 hypertensive participants, the combination diet reduced systolic and diastolic blood pressure by 11.4 and 5.5 mmHg (each P<0.001); in 326 non-hypertensive participants, corresponding reductions were 3.5 mmHg (P<0.001) and 2.1 mmHg (P=0.003). A diet rich in fruits, vegetables, and low-fat dairy foods, and reduced in saturated and total fat can substantially lower blood pressure. Such a diet offers an additional nutritional approach to prevent and treat hypertension.